<%
=begin
apps: jupyterhub
platforms: kubernetes, tanzu-application-catalog
id: understand_default_configuration
title: Understand the default configuration
category: get-started
weight: 40
highlight: 40
=end %>

The JupyterHub chart deploys three basic elements:

- JupyterHub: Central element of the chart. Manages authentication and is responsible for creating the Jupyter Notebook instances (called Single User instances). As a consequence, the Hub requires special RBAC privileges in order to access the Kubernetes API to create and manage Deployments.
- Proxy: This is the external endpoint for users. It manages the communication with the Hub and the Single User instances.
- Image Puller: In order to improve the Single User instance boot time, a DaemonSet object is deployed that pre-pulls all the necessary images to run the Single User Notebooks.

The following diagram shows a deployed release of the chart:

~~~
                                                         |
                                                         |
                                                         |
                                                         |
             ------------------                          |
             |                |                          |
             |  Image Puller  |<------Pull images to------
             |                |         all nodes
             ------------------

    -------------           ---------------
    |           |           |             |
    |   Proxy   |---------->|     Hub     |
    |           |           |             |
    -------------           ---------------
~~~

After accessing the hub and creating a Single User instance, the deployment looks as follows:

~~~
                                                         |
                                                         |
                                                         |
                                                         |
              ----------------                           |
             |                |                          |
             |  Image Puller  |<------Pull images to-----
             |                |         all nodes
              ----------------
    -----------             -------------
   |           |           |             |
   |   Proxy   |---------->|     Hub     |
   |           |           |             |
    -----------             -------------
        |                          |
        |                          |
        |                          |
        |     ---------------      |
        |     | Single User |      |
         ---->|  Instance   |<-----
              ---------------
~~~

For more information, check the official [JupyterHub documentation](https://github.com/jupyterhub/jupyterhub).
